1. Field of the Invention
This invention relates generally to rupturable pressure relief assemblies, and more particularly, but not by way of limitation, to rupturable pressure relief assemblies which are placed in systems containing fluids under pressure to insure relief in the event of an overpressure condition.
2. Description of the Prior Art
Many rupturable pressure relief assemblies and devices have been developed and used successfully heretofore. Generally, such devices include a rupture disk which is designed to rupture at a specific pressure range sealingly connected in an assembly which is in turn sealingly connected to a vessel or system containing fluids under pressure whereby the rupture disk is exposed to the fluid pressure. If the fluids within the vessel or system reach an overpressure condition, i.e., a pressure exceeding the design rupture pressure of the rupture disk, the disk ruptures thereby relieving fluids and pressure from the vessel or system.
In many applications of rupturable pressure relief assemblies, the volume and rate of fluids required to be relieved in order to alleviate overpressure is small. Thus, the rupturable pressure relief assemblies used in such applications can also be small. A number of small rupturable pressure relief assemblies which are preassembled by the manufacturer have been developed and used heretofore. An example of such an assembly is disclosed in U.S. Pat. No. 3,908,684 issued Sept. 30, 1975 and assigned to the assignee of this present invention. The rupture disk assembly disclosed includes a reverse buckling rupture disk clamped in a housing by means of a supporting member. The supporting member includes a deformable lip portion and is held in the housing by the upper end portion of the housing which is folded over the lip portion. The supporting member further includes a cutting means for severing the rupture disk upon its reversal. It is indicated in U.S. Pat. No. 3,908,684 that a variety of rupture disks can be utilized in the assembly other than reverse buckling rupture disks, e.g., flat disks and conventional concave-convex disks.
While rupture disk assemblies of U.S. Pat. No. 3,908,684 have achieved considerable success using reverse buckling rupture disks, it has been found that such assemblies using flat or conventional rupture disks are usually unsuccessful in that when fluid pressures are exerted thereon, the disks pull out from between the housing supporting shoulder and the supporting member causing the assemblies to malfunction or fail prematurely.
As is well understood by those skilled in the art, a reverse buckling disk includes a concave-convex portion with the convex side thereof exposed to fluids under pressure whereby upon failure, the concave-convex portion reverses itself and then ruptures. A conventional rupture disk includes a concave-convex portion and has the concave side exposed to fluids under pressure whereby the disk ruptures in tension. A flat disk also ruptures in tension.
By the present invention an improved small unitary rupturable pressure relief assembly is provided which can accommodate any type of rupture disk, i.e., reverse buckling, conventional or flat, without malfunction or premature failure occurring in the operation thereof due to the disk moving or pulling out of its clamped position in the housing.